Landau-fluid closures and their implementation in bout ++ with non-fourier methods

摘要

Summary form only given. The four-moment model which includes the evolution equation for the heat flux and the linear Hammett-Perkins (HP)1 closure for the fourth order moment is implemented based on the approximation by a sum of Lorentzian functions2 that allows fast conversion into the configuration space. An alternative set of closure relations based on the exact closures relations3 has also been developed and compared with HP closures1. In this approach the closures are used for the heat flux and viscosity moments represented in terms of the flow velocity and temperature perturbations. The practical closure expressions are obtained in form of the Pade approximants from the exact expressions. This approach is extended to include collisional effects4 using the exact closure obtained earlier5.